What to expect from Petraeus' confirmation hearings

[Update 3 p.m. ET] The Senate Armed Services Committee Tuesday approved the nomination of Gen. David Petraeus to be the top commander in Afghanistan.  The nomination now heads to the full Senate.

(CNN) - The planned withdrawal of troops from Afghanistan in 2011, along with with concerns over the progress of the counterinsurgency plan in a country described as a place "where empires go to die," will be front and center at Gen. David Petraeus' confirmation hearings Tuesday.

Petraeus was tapped by President Obama to replace Gen. Stanley McChrystal, who was relieved of his duties last week after the general and his staff were quoted in a Rolling Stone magazine article criticizing and mocking key administration officials.

But it's not just those comments that are making news - it's also conditions on the ground in Afghanistan.

More than two thirds of the additional troops the president ordered into Afghanistan in December are there now, but the Taliban's momentum is not broken and the price is high as U.S. troop deaths mount.

What to expect

Petraeus, commander of the U.S. Central Command, is almost certain to be confirmed by the Senate, observers note. He is well-respected and is often credited for turning the war in Iraq around.

While he's popular, the focus of the hearings before the Senate Armed Services Committee will more than likely focus on the progress - or the lack of it - in Afghanistan.

Problems with Afghanistan President Hamid Karzai's government, drug trafficking and the Taliban insurgency are some of the major challenges in the longest war in U.S. history.

A key question to come up: Obama's July 2011 deadline to start withdrawing troops. It's a source of contention between the president and Republican critics.

Petraeus recently told CNN's Dana Bash and Ted Barrett that he supports the president's policy and "will also provide the best professional military advice as we conduct assessments."

He was previously grilled by senators on the Armed Services Committee in June.

It is important that July 2011 be seen for what it is: the date when a process begins, based on conditions; not the date when the U.S. heads for the exits," he told the committee. "Moreover, my agreement with the president's decisions was based on projections of conditions in July 2011. And needless to say, we're doing all that is humanly possible to achieve those conditions."

The road ahead for Petraeus

U.S. military officials told CNN that Petraeus intends to undertake a sweeping review of American military operations in Afghanistan, including the rules of engagement for troops, if he is confirmed by the Senate.

The general told CNN that it's a privilege to serve, adding that it's "obviously a hugely important mission."

"It's very sad that I have to assume it in this manner," he said. "We all have enormous respect and gratitude to Gen. McChrystal for all that he did. He's played a key role in helping get the inputs right in Afghanistan."

Petraeus will also seek to find out if the troops simply need a better understanding of the rules or if the rules need to be changed, the sources noted.

If confirmed, Petraeus will have "the flexibility to make changes that he thinks are necessary," Joint Chiefs of Staff Chairman Adm. Mike Mullen said. "He's very aware of the issue of civilian casualties."

What observers are saying

Peter Bergen, CNN national security analyst in a CNN.com commentary:

"In Afghanistan, Petraeus must convince all sorts of constituencies, from the Afghan people, to the Pakistani military and political establishment, to the White House, to the American public, that some plausible progress is being made; that the Americans are not going to "cut and run" before a semistable Afghan government and military are in place. And he must do that all on a timetable in which some kind of American drawdown begins in July 2011."

Fareed Zakaria, host of CNN's "Fareed Zakaria GPS":

"This is a masterstroke. Petraeus needs no on-the-job training, knows the theater and is beloved by the troops. He understands COIN [counter-insurgency strategy], literally wrote the book on it, and most important - knows how to execute it. He has superb political skills and understands that a close working relationship with his civilian counterparts from the State Department, White House and other agencies is not a bother but at the heart of the mission's success."

Sen. Carl Levin, D-Michigan, on CBS's "Face the Nation" Sunday:

Petraeus has "a very great capability of bringing people together. He has shown that he's able to bring together our civilian side in Afghanistan. He's shown that in Iraq when he was able to do that. And he's going to be able, I believe, to do that in Afghanistan. ... I think he can improve that situation."

Sen. Saxby Chambliss, R-Georgia, on CNN's "State of the Union" with Candy Crowley on Sunday:

"Right now, Gen. Petraeus comes in with his team of military leaders. They have got to work hand-in-hand with the civilian side."

Sen. Jack Reed, D-Rhode Island, also on "State of the Union":

"Gen. Petraeus will get on the ground. And he has been very effective in pulling together in Iraq not only the American effort but also the effort of the host country. And I think he will be equally successful in Afghanistan. I think everyone recognizes, both the civilian side and military side, that there has to be a unified effort, there has to be a concentration on assisting the Afghanis. But ultimately this is going to be the Afghanis' effort."

Sen. John McCain, R-Arizona, on NBC's "Meet the Press" on Sunday:

"The point is that Gen. Petraeus is put in an almost untenable position here."

Tom Friedman, Pulitzer Prize-winning New York Times columnist on "GPS" on Sunday:

"I hope so [that Petraeus will be able to stabilize things.] As an American, you know, I hope so ... our troops are there, we certainly have stakes. But as you know, I've been dubious about this from the beginning."

CNN's Candy Crowley, Mike Mount and Barbara Starr contributed to this report.